/*
 * Copyright (c) 1997, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
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 *
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 *
 *
 */

package java.awt.geom;

import java.util.*;

/**
 * A utility class to iterate over the path segments of a rectangle
 * through the PathIterator interface.
 *
 * @author Jim Graham
 */
class RectIterator implements PathIterator {

  double x, y, w, h;
  AffineTransform affine;
  int index;

  RectIterator(Rectangle2D r, AffineTransform at) {
    this.x = r.getX();
    this.y = r.getY();
    this.w = r.getWidth();
    this.h = r.getHeight();
    this.affine = at;
    if (w < 0 || h < 0) {
      index = 6;
    }
  }

  /**
   * Return the winding rule for determining the insideness of the
   * path.
   *
   * @see #WIND_EVEN_ODD
   * @see #WIND_NON_ZERO
   */
  public int getWindingRule() {
    return WIND_NON_ZERO;
  }

  /**
   * Tests if there are more points to read.
   *
   * @return true if there are more points to read
   */
  public boolean isDone() {
    return index > 5;
  }

  /**
   * Moves the iterator to the next segment of the path forwards
   * along the primary direction of traversal as long as there are
   * more points in that direction.
   */
  public void next() {
    index++;
  }

  /**
   * Returns the coordinates and type of the current path segment in
   * the iteration.
   * The return value is the path segment type:
   * SEG_MOVETO, SEG_LINETO, SEG_QUADTO, SEG_CUBICTO, or SEG_CLOSE.
   * A float array of length 6 must be passed in and may be used to
   * store the coordinates of the point(s).
   * Each point is stored as a pair of float x,y coordinates.
   * SEG_MOVETO and SEG_LINETO types will return one point,
   * SEG_QUADTO will return two points,
   * SEG_CUBICTO will return 3 points
   * and SEG_CLOSE will not return any points.
   *
   * @see #SEG_MOVETO
   * @see #SEG_LINETO
   * @see #SEG_QUADTO
   * @see #SEG_CUBICTO
   * @see #SEG_CLOSE
   */
  public int currentSegment(float[] coords) {
    if (isDone()) {
      throw new NoSuchElementException("rect iterator out of bounds");
    }
    if (index == 5) {
      return SEG_CLOSE;
    }
    coords[0] = (float) x;
    coords[1] = (float) y;
    if (index == 1 || index == 2) {
      coords[0] += (float) w;
    }
    if (index == 2 || index == 3) {
      coords[1] += (float) h;
    }
    if (affine != null) {
      affine.transform(coords, 0, coords, 0, 1);
    }
    return (index == 0 ? SEG_MOVETO : SEG_LINETO);
  }

  /**
   * Returns the coordinates and type of the current path segment in
   * the iteration.
   * The return value is the path segment type:
   * SEG_MOVETO, SEG_LINETO, SEG_QUADTO, SEG_CUBICTO, or SEG_CLOSE.
   * A double array of length 6 must be passed in and may be used to
   * store the coordinates of the point(s).
   * Each point is stored as a pair of double x,y coordinates.
   * SEG_MOVETO and SEG_LINETO types will return one point,
   * SEG_QUADTO will return two points,
   * SEG_CUBICTO will return 3 points
   * and SEG_CLOSE will not return any points.
   *
   * @see #SEG_MOVETO
   * @see #SEG_LINETO
   * @see #SEG_QUADTO
   * @see #SEG_CUBICTO
   * @see #SEG_CLOSE
   */
  public int currentSegment(double[] coords) {
    if (isDone()) {
      throw new NoSuchElementException("rect iterator out of bounds");
    }
    if (index == 5) {
      return SEG_CLOSE;
    }
    coords[0] = x;
    coords[1] = y;
    if (index == 1 || index == 2) {
      coords[0] += w;
    }
    if (index == 2 || index == 3) {
      coords[1] += h;
    }
    if (affine != null) {
      affine.transform(coords, 0, coords, 0, 1);
    }
    return (index == 0 ? SEG_MOVETO : SEG_LINETO);
  }
}
